Vagus Nerve Stimulation
Vagus nerve stimulation is a therapeutic treatment that sends electric signals to the brain through a small device that is implanted underneath the skin of the chest. This device, known as as a vagus nerve stimulator, sends pulses of electrical energy to the vagus nerve and to the brain, which helps to inhibit seizures in many patients with epilepsy. The vagus nerve is one of twelve cranial nerves in the brain, and it sends messages from the brain to the body's major organs including the heart, lungs and intestines, and to areas of the brain that control mood, sleep, and other functions. Some research has indicated that when stimulated by electrical impulses, the vagus nerve sends messages to the brain that help to stop seizures from occurring, and may also help to control mood in people suffering from depression.
Candidates for Vagus Nerve Stimulation
Vagus nerve stimulation may be an effective therapy for people with epilepsy who have not responded to anti-seizure medication. It may also be used to treat patients with severe depression who have not responded to medication or psychological counseling. Although it may not be effective in all individuals, many patients with epilepsy experience a significant reduction in the number and frequency of seizures with this treatment.
The Vagus Nerve Stimulation Procedure
Initially, surgery is performed to implant the vagus nerve stimulation device into the upper left area of the chest. While the patient is sedated under general anesthesia, an incision is made in the chest and the device is implanted along with a connecting wire that runs under the skin to the vagus nerve in the neck. This procedure usually takes about 1 to 2 hours to perform. A few weeks after the implantation surgery, the doctor will program the stimulation device to deliver electrical impulses to the vagus nerve at varying frequencies and currents. Depending on symptoms and the severity of the individual's condition, the vagus nerve stimulation may start at a low level and is gradually increased. Patients may also be given their own magnetic device to control the stimulation themselves.
Risks of Vagus Nerve Stimulation
While the implantation procedure is considered safe for most patients, there is a risk of injury to the vagus nerve, carotid artery and jugular vein. Possible complications may also include infection and bleeding. While the nerves are being stimulated through the vagus nerve stimulation process, complications may include:
- Swallowing difficulties
- Tingling sensation in the neck
- Breathing problems(especially during exercise)
- Throat pain
Some complications or side effects may decrease over time, however, adjusting the electrical impulses may also help to minimize these effects.
Results of Vagus Nerve Stimulation
While vagus nerve stimulation may not completely stop seizures in patients with epilepsy, many individuals do experience a reduction in the number of seizures that they experience. It may also take up to 2 years for epilepsy patients to notice any significant relief of symptoms from the use of vagus nerve stimulation. Research varies on whether vagus nerve stimulation is an effective method of treatment for depression. Patients may need several months of treatment before noticing any improvement in the symptoms of depression.
Vagus nerve stimulation may not be an effective treatment for all patients and is not meant to replace traditional treatments for the associated conditions.